Congenital Malformations of Pulmonary and Intestinal Lymphatic Flow
Complications of congenital malformations of lymphatic flow include chylous effusions (thoracic cavity), chylous ascites (peritoneal cavity) and, even more rarely, chylopericardium (pericardial cavity). These complications are often seen in children with complex vascular anomalies including generalized lymphatic anomalies (GLA), central conducting lymphatic anomalies (CCLA), Gorham Stout disease (GS), and Kaposiform lymphangiomatosis (KLA, a proliferative disorder) (Table 1) or in children with known congenital syndromes associated with malformed lymphatics including Down, Turner and Noonan syndromes. These complications of lymphatic flow can result in systemic fluid and electrolyte imbalance, nutritional deficiencies, hypovolemia, and hypoalbuminemia. Progressive loss of essential proteins results in an increased risk of hemorrhagic coagulopathy from lack of prothrombin and fibrinogen.[3] Thrombophilia can occur due to loss of antithrombin. There is an additional increased risk of infection from the loss of both cellular (lymphocytopenia and low CD4+ T-cells) and humoral (hypogammaglobulinemia) immunity resulting in progressive immunosuppression.[4]
Congenital lymphatic leak can occur in utero due to obstructions and leaks of the lymphatic system. The accumulation of large fluid volumes in the thorax or abdomen can lead to cardiac failure and obstruction of venous return leading to non-immune hydrops fetalis, polyhydramnios, and fetal demise. Historically, mortality for congenital chylothorax has been reported to be high around 10-20%.[5, 6] New imaging, surgical and interventional techniques have reduced mortality significantly in certain populations.[7]